Schramm interrupted his education to serve as an officer in the United States Army Air Forces during World War II.

During his tenure, he hired Pete Rozelle as the Rams' public relations director, who would eventually become the Commissioner of the National Football League.

They remained close friends after Rozelle became NFL commissioner and Schramm became general manager of the Cowboys (each holding his position for 29 years).

In late 1959, when it became apparent that the NFL was intent on expanding to Dallas, Schramm told his friends in football that he was interested in running the team.

Chicago Bears owner George Halas introduced Schramm to Clint Murchison Jr., who had tried to bring the NFL to Dallas several times in the past.

Murchison hired Schramm as the general manager for a potential Dallas team, which became a reality when the league awarded a franchise to the city on January 28, 1960.

The Cowboys' owners during his tenure, Murchison (1960–84) and Bum Bright (1984–1988), largely left day-to-day operations in his hands.

Running back Tony Dorsett, who had previously criticized other team members for breaking the strike, felt he was financially forced to rejoin as well by Schramm's threats.

These include instant replay, using computer technology in scouting, multi-color striping of the 20- and 50-yard lines, 30-second clock between plays, extra-wide sideline borders, wind-direction stripes on the goal post uprights, the referee's microphone, headsets in the quarterback's helmet for hearing plays, and hiring Dee Brock to establish the Dallas Cowboys Cheerleaders.